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lewis_willy2
17-02-2008, 17:40
ok clio turbo gurus, need some help

im going to make my own downpipe?

i would like pics so i can see how many bends etc there are. im on a really tight budget due to buying a house and due to my downpipe i had already purchased getting lost in the post :evil: i refuse to pay someone £300 to make me 1.

i know a sh@t hot welder so all i need is pipe work, does anyone know a good place to buy exhaust bends etc.

if anyone has a downpipe which they plan to use in the future but isnt currently on their car could i burrow it to make a copy? i know its a tall order, but worth a shot.

any help appreciated

lewis

Lunner
17-02-2008, 19:43
Jetex do bends etc although usually they'll cut the pipe on the angle and weld to give the bend, so a bend if made up of several segments

lewis_willy2
17-02-2008, 19:49
my welder friend is going to get me a price 2mro morning on a length of stainless pipe. how thick do i want the wall and what diameter of pipe shall i get. just gotta find the correct flanges

Coops
17-02-2008, 21:08
stick to 2.5 inch at least mate,i havent actually got any pics of mine i dont think am afraid and its on the car atm, sorry dude

lewis_willy2
17-02-2008, 21:14
no probs m8, prob gonna have to just do some guessing until its right!!

Coops
17-02-2008, 21:16
well since i fitted the disco potatoe it doesnt fit right anyway :lol: would catch on the subframe if i didnt have my Coops (tm) solid adjustable dogbone on (all rights reserved, patent could be pending) :lol: :wink:

MAXIBOY
17-02-2008, 21:23
mine fits great but am also struggling to find pics mate. but i,m still looking..

Coops
17-02-2008, 21:46
think yours is updated design tho neil mate, mine was for original conversions done on 270 degree bearing t28, the gt28rs is larger exhaust housing that throws the exhaust further off to one side, so thats why mines a bit dodgy

alex_blue16v
17-02-2008, 22:07
Just took these for you,

first one is as if you were looking from the front through the block
second one is sideways on
and third one is as if from above


http://img166.imageshack.us/img166/1452/dsc00287ae3.jpg

http://img166.imageshack.us/img166/5445/dsc00286iv5.jpg

http://img166.imageshack.us/img166/6049/dsc00288gj3.jpg

its the prima downpipe and is missing the flange that bolts to the turbo as i havent had that welded on yet but hope it helps a bit dude

donsrno1
17-02-2008, 22:54
http://img166.imageshack.us/img166/6049/dsc00288gj3.jpg


Nice socks :lol:

kj16v
17-02-2008, 23:03
Here's mine. Bends are from Dynoflow. Unlike all the ones made by various tuning companies, mine's got a flexi-joint so it doesn't cause problems with the exhaust. The turbo flanges come from Ebay. Don't go for XS-Power/SS-Autochrome because they're chromed mild-steel labelled up as stainless.

Coop's: was thinking, yours would might fit if it had a flexi-joint. Gives a bit of leway.

http://img523.imageshack.us/img523/7952/myturbodownpipe1rd2.th.jpg (http://img523.imageshack.us/my.php?image=myturbodownpipe1rd2.jpg)

http://img153.imageshack.us/img153/5426/myturbodownpipe2uy6.th.jpg (http://img153.imageshack.us/my.php?image=myturbodownpipe2uy6.jpg)

Coops
17-02-2008, 23:05
where ur flexi is mate is where mine catches, av thought about puttin one in but the dogbone i made has all but solved it so av not bothered :lol:

mad lookin sidepipe on yours for top of turbo flange bit :twisted:

lewis_willy2
17-02-2008, 23:25
awsome pics, that'll help loads ta.

was thinking about venting the wastegate gases to atmosphere instead of back into the downpipe, is this a good or bad idea? what are the pro's and cons?

Coops
17-02-2008, 23:28
tough to do with a internal wastegate mate, lots of extra hassle, i wouldnt bother personally, if it does sap bhp venting into normal exhaust stream then i havent noticed, lmao

lewis_willy2
17-02-2008, 23:40
how long do you reckon i need in pipe?

also this is what im thinking of doing?

http://cgi.ebay.co.uk/Nissan-180SX-S14-SR20DET-Turbo-Elbow-Screamer-Pipe_W0QQitemZ180216704658QQihZ008QQcategoryZ38786 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Flan
18-02-2008, 11:01
I've got the std BB tuning one and i must say the quality is spot on! and fits perfect. also there fiberglass heat shield is spot on!

lewis_willy2
18-02-2008, 11:38
bb tuning are a waste of time imo. but would buy the downpipe if they had them. i did have one on route until the royal mail c@cked up. and a throttle adapter!

Scougar
18-02-2008, 11:38
XS-power/autochrome are a rubbish company anyway, never ever buy a turbo from them. However, mild steel is more resilient to high temps than stainless (as I understand it), so it isn't such a bad idea to have mild.

Also, never ever, weld with stainless on mild, it will crack guaranteed.

Matthew

lewis_willy2
18-02-2008, 11:49
i best make sure i get stainless flanges then. when i can find some!!!

can someone measure the lenth of the pipe so i know how much to order. so far ive got prices on 1m lengths and 4m lengths!!!

if any one wants a downpipe made, pm me as i may get a couple bent if i can only source 4m length

Flan
18-02-2008, 12:30
Where you from! i get all my bends from a place in Brackley. They do loads a race exhausts. 1m should be about £19 each bend is £20 iirc

lewis_willy2
18-02-2008, 12:36
im just after a 2m length and the flanges. whats the company called and do they supply flanges?

dhay14
18-02-2008, 12:45
bb tuning are a waste of time imo. but would buy the downpipe if they had them. i did have one on route until the royal mail c@cked up. and a throttle adapter!

I have mailed BB a couple of time now for info on the downpipe and other parts and still no reply... :?

kj16v
18-02-2008, 13:23
XS-power/autochrome are a rubbish company anyway, never ever buy a turbo from them. However, mild steel is more resilient to high temps than stainless (as I understand it), so it isn't such a bad idea to have mild.

Also, never ever, weld with stainless on mild, it will crack guaranteed.

Matthew

D'oh too late! :droool: Agree with everything you said there. Fortunately mines fine.

Lews: I first started out with the same setup as that Nissan flange, and I can assure you it sounds ATTROCIOUS!! Was easier to build cuz of the shape of the outlet flange but was really embarrasing. Just driving slowly round town had people stopping and staring. Somebody was taking their puppy for a walk and the poor thing went mad! Yapping and tearing around nearly strangled itself on the lead! :oops:
Plum it all in - unless you like that sort of thing!

lewis_willy2
18-02-2008, 13:34
can anyone lend me a downpipe?

got a quote on bending but really could do with a downpipe to copy, or the correct dimensions would be great? just waiting on stainless prices. gonna get a few knocked up to help others out, so if you want an exhaust bent up then contact me before the end of the week before i order the stainless.

kj16v
18-02-2008, 13:43
Where you from! i get all my bends from a place in Brackley. They do loads a race exhausts. 1m should be about £19 each bend is £20 iirc

Hey, blighmey didn't know you were still on here! How's the Nissan-engine kit car going?

www.Dynoflow.co.uk is much cheaoer than that. Plus the more you buy, the cheaper they are.

Remember that clutch we put in? Lasted all of three months! have a more substantial Sachs clutch now. Have a feeling that won't last too long either. Just can't find anything man enough for the job!

alex_blue16v
18-02-2008, 14:06
kj, when you say you used the nissan flange setup what do you mean cos ive got this one,
http://cgi.ebay.com/ebaymotors/T25-T28-TD04-H-GT28RS-downpipe-turbo-weld-flange-CNC_W0QQcmdZViewItemQQcategoryZ33742QQihZ001QQitem Z110224024770QQrdZ1QQsspagenameZWDVW

i dont want spend all this time and effort for it to sound poo

alex_blue16v
18-02-2008, 14:10
kj, when you say you used the nissan flange setup what do you mean cos ive got this one,
http://cgi.ebay.com/ebaymotors/T25-T28-TD04-H-GT28RS-downpipe-turbo-weld-flange-CNC_W0QQcmdZViewItemQQcategoryZ33742QQihZ001QQitem Z110224024770QQrdZ1QQsspagenameZWDVW

i dont want spend all this time and effort for it to sound poo

lewis_willy2
18-02-2008, 14:13
i think he meant like this

http://cgi.ebay.co.uk/Nissan-180SX-S14-SR20DET-Turbo-Elbow-Screamer-Pipe_W0QQitemZ180216704658QQihZ008QQcategoryZ38786 QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

with the wastegate going to atmosphere.



i have just had a call and i can get 60mm tubing at a good price and my friend can bend in house to keep cost down. is 60mm going to be sufficient?

alex_blue16v
18-02-2008, 14:17
aaaah i see now.

60mm should be fine i think, mines 2.5 inch as far as i know.

Scougar
18-02-2008, 15:49
Lews: I first started out with the same setup as that Nissan flange, and I can assure you it sounds ATTROCIOUS!! Was easier to build cuz of the shape of the outlet flange but was really embarrasing. Just driving slowly round town had people stopping and staring. Somebody was taking their puppy for a walk and the poor thing went mad! Yapping and tearing around nearly strangled itself on the lead! :oops:
Plum it all in - unless you like that sort of thing!

It's called a "Screamer Pipe" if you vent the wastegate to atmosphere, and yes, it is noiser and is only worthwhile doing on an external wastegate setup.

One thing to note though is that you obviously hadn't got the wastegate set up correctly. Unless it is on full boost the wastegate should not have been opening, meaning your's was. When driving normally -without full boost and no wastegate - it should have been like normal, possibly making an occasional blow off. It should not under any circumstances have been opening the wastegate when turning round or parking for example.

Matthew

lewis_willy2
18-02-2008, 19:34
right i can get a mild steel downpipe made up real cheap.

its gonna be 60mm diameter with wall thickness of 3mm. is this a bad idea. i understand stainless will be better but am on a tight budget at the mo.


however i am looking at making 3 stainless steel ones in 2.5inches with a wall thickness of 1.6mm im just looking for flanges then i will have prices.

kj16v
19-02-2008, 00:30
One thing to note though is that you obviously hadn't got the wastegate set up correctly. Unless it is on full boost the wastegate should not have been opening, meaning your's was. When driving normally -without full boost and no wastegate - it should have been like normal, possibly making an occasional blow off. It should not under any circumstances have been opening the wastegate when turning round or parking for example.

Matthew

It's because mine has an internal wastegate and there was nothing between that and the exducer. So the exhaust from the exducer took the easy way out through the short screamer pipe. My first exhaust setups were pants. I've only just got it right with the final design pictured above.


Alex: That flange is OK. Will make things much easier with one round hole. BUT It's a bit crap gas flow-wise. The gas from the wastegate will hit a dead-end and have to force it's way out, which will increase back-pressure. How much of a difference this will make in the real world I don't know. If it really bothers you it won't take much to mill out a 1.5" hole for a seperate pipe.

lewis_willy2
19-02-2008, 09:04
so just to confirm, a mild steel flange will be ok if using stainless pipe?

ive just been quoted £30 for stainless t28 flanges

Scougar
19-02-2008, 10:54
It's because mine has an internal wastegate and there was nothing between that and the exducer. So the exhaust from the exducer took the easy way out through the short screamer pipe. My first exhaust setups were pants. I've only just got it right with the final design pictured above.

Right that makes sense why that was happening then :) You can get turbo's with internal wastegate and a 'partial' barrier around the wastegate, but it is more trouble than it is worth, and modding the housing can cause other problems. I know it is more expensive, but you are much better off going for external wastegate, or get a decent downpipe area to start with. 2L turbos running near 400BHP often still use a very simple all in one turbo downpipe for internal wastegate turbo's, because it has less issues. Not saying anything wrong with your current design, just might be more complicated than you really need.

BTW, for flan. There is a common problem with the T28 nissan turbo gasket that being filled with some heat resistant compound, breaks down over time. These often are a nightmare to change, so make sure you also use decent locking nuts if ever using that again :) (The sound to listen for is if your car sounds like a diesel or a tractor ;) )

Matthew